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Zaffar A, Jayaraman S, Sutar PP, Balasubramanian P. Comparative evaluation of drying methods for struvite produced from electrocoagulated source-separated urine: Implications for quality, energy and cost-effectiveness. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 356:120665. [PMID: 38518498 DOI: 10.1016/j.jenvman.2024.120665] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/25/2023] [Revised: 02/19/2024] [Accepted: 03/11/2024] [Indexed: 03/24/2024]
Abstract
Struvite precipitation from source-separated urine is crucial for waste utilization and sustainability. However, after precipitation, the high moisture content of struvite necessitates an additional drying process that can be costly and inefficient. In the present study, the performance of different drying methods-open sun drying, air drying, conventional drying (20-100 °C), and microwave drying (180-720 W) on the quality of struvite obtained from source-separated urine through electrocoagulation using Mg-Mg electrodes were evaluated. It was found that higher temperatures and power in the convective oven and microwave resulted in higher diffusivity (10-9-10-7 m2s-1), leading to reduced drying times. Different models were employed to comprehend the drying mechanism, and the one with the highest correlation coefficient (R2 = 0.99) and the lowest statistical values was selected. The key findings indicated that higher power and temperature levels were more cost-effective. However, characterization of the dried struvite using X-ray diffraction and Fourier-transformed infrared spectroscopy, disintegration of struvite crystals at temperatures above 60 °C in the conventional oven and 180 W in the microwave oven was observed. Based on the results, we conclude that sun drying is a cost-effective and environmentally friendly alternative for drying struvite without compromising its quality.
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Affiliation(s)
- Alisha Zaffar
- Department of Biotechnology and Medical Engineering, National Institute of Technology Rourkela, Odisha, -769008, India
| | - Sivaraman Jayaraman
- Department of Biotechnology and Medical Engineering, National Institute of Technology Rourkela, Odisha, -769008, India
| | - Parag Prakash Sutar
- Department of Biotechnology and Medical Engineering, National Institute of Technology Rourkela, Odisha, -769008, India
| | - Paramasivan Balasubramanian
- Department of Biotechnology and Medical Engineering, National Institute of Technology Rourkela, Odisha, -769008, India.
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2
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Convection Drying Influence on Thermo-Physical Properties, Bioactive Substances, Color and Texture Profile of Red Pepper ( Capsicum Spp). ACTA UNIVERSITATIS CIBINIENSIS. SERIES E: FOOD TECHNOLOGY 2022. [DOI: 10.2478/aucft-2022-0007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Abstract
This work aimed to study the effect of convection drying on bioactive substances and on the texture profile of red pepper. Four mathematical models were used to model the drying kinetics, as a function of the temperature and the thickness of slices. These models are largely in agreement with experimental data. Effective diffusivity, Arrhenius constant, activation energy and thermal properties changed with temperature of dry process. The two varieties of pepper used in this work demonstrated a very high degree of spiciness (144799.37-160899.37 SU). This property is related to the high contents of capsaicin (39.60-44.01 mg/g) and dihydrocapsaicin (32.33-35.95 mg/g). Our results revealed that brittleness, hardness 1 and 2, firmness, chewiness, gumminess appearance and Young’s modulus are very important attributes in determining the textural profile of dried red pepper. Also, drying causes a strong degradation of natural pigments of red pepper and consequently decreases attractiveness of the texture profile. To avoid that, red pepper should be pretreated before the application of hot air drying.
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Analytical evaluation of carotenoids, apocarotenoids, capsaicinoids, and phenolics to assess the effect of a protective treatment on chili peppers dried at different temperatures. Eur Food Res Technol 2022. [DOI: 10.1007/s00217-022-04049-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
AbstractThe most common preservation process for chili peppers is drying, which inevitably causes oxidative degradation of thermolabile molecules. The aim of this research was to evaluate the potential protective effect exerted by an active ingredient based on grape seed oil, on pepper fruits. Grapeseed oil is rich in antioxidant compounds and was applied to pepper’s surface in form of a sol–gel product, before fruit thermal treatment. In this work, chili peppers samples were preventively treated with an active solution, and controls (untreated peppers), were submitted to a drying process performed at two different temperatures: 45 and 65 °C. Analysis of capsaicinoids, carotenoids, apocarotenoids, and phenolic content was performed to evaluate possible differences between the sets of samples. Oxidative stability of oil enriched with chili pepper powder aliquots was also measured to evaluate the antioxidant power of the samples. Obtained data showed that treated samples retained a higher amount of capsaicinoids and carotenoids. Oxidative stability of pepper powder was also higher for treated samples than for controls. Furthermore, the thermal treatment performed at 45 °C caused milder modifications than the 65 °C treatment. The applied pre-drying treatment can be proposed to prevent bioactive compounds loss and to enhance product stability and shelf-life.
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Kumar N, Pratibha, Neeraj, Sami R, Khojah E, Aljahani AH, Al-Mushhin AAM. Effects of drying methods and solvent extraction on quantification of major bioactive compounds in pomegranate peel waste using HPLC. Sci Rep 2022; 12:8000. [PMID: 35568719 PMCID: PMC9107484 DOI: 10.1038/s41598-022-11881-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Accepted: 04/20/2022] [Indexed: 12/24/2022] Open
Abstract
Bioactive compound characterization is an essential step for utilizing pomegranate peel waste as food and nutraceuticals ingredients. In the present investigation, the effects of different drying methods (freeze, tray-oven, and sun) and extraction solvents such as methanol, ethanol, water, acetone, and hexane were investigated on the extraction and recovery of major bioactive compounds (ellagic acid, gallic acid, quercetin, and punicalagin) of pomegranate peel for two pomegranate varieties (i.e., Bhagwa and Ganesh) using high-performance liquid chromatography (HPLC). The results indicated that the freeze dried pomegranate peel powder of both pomegranate varities potential to extraction higher amount of bioactive compounds with methanol as extraction solvent as compared to other drying methods and solvents. Freeze-dried peel powder of Bhagwa pomegranate showed a higher amount of gallic acid (32.2 mg/g), ellagic acid (13.6 mg/g), punicalagin (15.2 mg/g), and quercetin (2.5 mg/g) with methanol solvent as compared to the other extract of Bhagwa and Ganesh varieties. The basis on the results of the current study, it can be concluded that the freeze-drying method of drying pomegranate peel powder and methanol as an extraction solvent are effective to recover higher amounts of bioactive compounds that can be utilized in food and pharmaceutical sectors at commercial scale.
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Affiliation(s)
- Nishant Kumar
- National Institute of Food Technology Entrepreneurship and Management (NIFTEM), Plot No. 97, Sector- 56, HSIIDC, Industrial Estate, Kundli, Sonipat, Haryana, 131028, India
| | - Pratibha
- National Institute of Food Technology Entrepreneurship and Management (NIFTEM), Plot No. 97, Sector- 56, HSIIDC, Industrial Estate, Kundli, Sonipat, Haryana, 131028, India.,National Institute of Technology Delhi, Plot No. FA7, Zone, P1, GT Karnal Road, Delhi, 110036, India
| | - Neeraj
- National Institute of Food Technology Entrepreneurship and Management (NIFTEM), Plot No. 97, Sector- 56, HSIIDC, Industrial Estate, Kundli, Sonipat, Haryana, 131028, India.
| | - Rokayya Sami
- Department of Food Science and Nutrition, College of Sciences, Taif University, P.O. 11099, Taif, 21944, Saudi Arabia.
| | - Ebtihal Khojah
- Department of Food Science and Nutrition, College of Sciences, Taif University, P.O. 11099, Taif, 21944, Saudi Arabia
| | - Amani H Aljahani
- Department of Physical Sport Science, College of Education, Princess Nourah bint Abdulrahman University, P.O. Box 84428, Riyadh, 11671, Saudi Arabia
| | - Amina A M Al-Mushhin
- Department of Biology, College of Science and Humanities in Al-Kharj, Prince Sattam Bin Abdulaziz University, Al-Kharj, 11942, Saudi Arabia
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5
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Drying kinetics of blueberry pulp and mass transfer parameters: Effect of hot air and refractance window drying at different temperatures. J FOOD ENG 2022. [DOI: 10.1016/j.jfoodeng.2021.110929] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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6
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Physico-Chemical Properties of Red Pepper (Capsicum annuum L.) as Influenced by Different Drying Methods and Temperatures. Processes (Basel) 2022. [DOI: 10.3390/pr10030484] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
An experiment was carried out in the laboratories of the Department of Food Engineering, Department of Vegetable Science, and Department of Plantation Spices Medicinal and Aromatic crops, Bidhan Chandra Krishi Viswavidyalaya (BCKV), West Bengal, India. The work was performed during 2018–2019 and 2019–2020 with different drying methods including sun drying, solar drying and oven drying. In oven drying, different temperatures such as 50, 55, 60, 65, and 70 °C were considered. A randomized complete block design (RCBD) was designed with seven treatments and three replications. Experimental results were significantly varied among the treatments as influenced by different drying methods and temperatures. Minimum time taken (480 min) to reach safe moisture content was recorded in T7 (oven drying at 70 °C), whereas maximum values in color components such as L* value (24.55), a* value (32.14), b* value (20.53), and pungency score (7.85) were recorded in T6 (oven drying at 65 °C). However, the highest texture (1180.81) was observed in T1 (sun drying). Biochemical parameters were significantly varied among the treatments. The maximum amounts of ascorbic acid (56.06 mg/100 g) and oleoresin content (10.72) were found in T3 (oven drying at 50 °C), whereas minimum values of biochemical parameters were recorded by T1 (sun drying) and T2 (solar drying) methods, respectively. Mathematical relationships were found in different drying methods and temperatures. Models such as the Lewis, Page, Modified Page, and Henderson and Pabis models were selected to fit the data. Maximum R2 value (0.9835) was found in both the Page and Modified Page models with similar values of drying method and temperature at 65 °C. This value was the highest among all models in all drying temperatures. However, the lowest χ2, and RMSE values (0.000818 and 0.027261, respectively) were recorded with the Page model.
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Pulsed Vacuum Drying of Pepper ( Capsicum annuum L.): Effect of High-Humidity Hot Air Impingement Blanching Pretreatment on Drying Kinetics and Quality Attributes. Foods 2022; 11:foods11030318. [PMID: 35159468 PMCID: PMC8834486 DOI: 10.3390/foods11030318] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2022] [Revised: 01/19/2022] [Accepted: 01/22/2022] [Indexed: 02/01/2023] Open
Abstract
With a high moisture content, fresh peppers are perishable and rot easily. Drying is essential for shelf-life extension. The natural thin wax layer on the pepper surface hinders moisture transfer. Traditionally, chemical dipping or mechanical pricking is used to remove this wax layer. However, in chemical dipping, chemical residues can trigger food-safety issues, while the low efficiency of mechanical pricking hinders its industrial application. Feasible pretreatment methods are advantageous for industrial use. Here, an emerging pretreatment technique (high-humidity hot-air impingement blanching, HHAIB) was used for peppers before drying and its effects on drying characteristics, microstructure, and polyphenol oxidase (PPO) activity were explored. The impact of drying temperature on color parameters and red pigment content of pulsed-vacuum-dried peppers was also evaluated. PPO activity was reduced to less than 20% after blanching at 110 °C for 60 s. HHAIB reduced drying time and PPO activity and promoted chemical-substance release. Effective water diffusivity was highest (5.01 × 10-10 m2/s) after blanching at 110 °C for 90 s, and the brightness value and red pigment content were highest (9.94 g/kg) at 70 °C. HHAIB and pulsed vacuum drying are promising pretreatment and drying methods for enhancing the drying rate and quality of red peppers.
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PANTOJA ESPINOSA DC, RODRÍGUEZ CORTINA J, HERNÁNDEZ CARRIÓN M, OSORIO MORA O. Drying and cooking effects on the final quality of pea grains (Pisum sativum L.) varieties. FOOD SCIENCE AND TECHNOLOGY 2022. [DOI: 10.1590/fst.32120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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9
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Boadu VG, Essuman EK, Otoo GS, Bigson K. The Impact of Different Drying Techniques on the Physicochemical and Quality Characteristics of Oil Palm Fruit Mesocarp ( Elaeis guineensis). INTERNATIONAL JOURNAL OF FOOD SCIENCE 2021; 2021:2005502. [PMID: 34977232 PMCID: PMC8719984 DOI: 10.1155/2021/2005502] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/03/2021] [Accepted: 12/10/2021] [Indexed: 11/17/2022]
Abstract
Drying is one of the traditional means of preserving food. However, various drying methods can influence the nutritional and bioactive constituents of the food product. This study is aimed at evaluating the effect of different drying methods on the proximate composition, physicochemical properties, and minor constituents of palm oil fruit mesocarp. Two varieties of fresh oil palm fruit (dura and tenera) were processed to separate the mesocarp from the other part of the fruit. The fresh fruit mesocarp was divided into five groups and subjected to different drying methods. Proximate and physicochemical characteristics of the oil palm fruit mesocarp were determined. The dried mesocarp had low moisture content (1.49-3.28%), high crude fat content (78.10-90.60%), carbohydrate (4.41-15.12%), crude protein (0.93-3.40%), and ash (0.53-1.15%). The free fatty acid (FFA) (1.06-3.54) and acid value (AV) (2.17 to 8.83 mgKOH/g) were lower because the samples were heated at 100°C for 30 min. The lower pH, FFA, AV, titratable acidity, moisture content, and high antioxidant activity of the oil palm fruit products could be an indication of shelf stability against microbial contamination and rancidity.
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Affiliation(s)
- Vida Gyimah Boadu
- Department of Hospitality and Tourism Education, Akenten Appiah-Menka University of Skills Training and Entrepreneurial Development, Kumasi, Ghana
| | - Edward Ken Essuman
- Department of Nutrition and Dietetics, School of Allied Health Sciences, University of Health and Allied Sciences, Ho, Ghana
| | - Gifty Serwaa Otoo
- Department of Food Science and Postharvest Technology, Cape Coast Technical University, Cape Coast, Ghana
| | - Kate Bigson
- Department of Hotel, Catering and Institutional Management, Dr. Hilla Limann Technical University, P.O. Box 553, Wa, Ghana
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10
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Lemus-Mondaca R, Zura-Bravo L, Ah-Hen K, Di Scala K. Effect of drying methods on drying kinetics, energy features, thermophysical and microstructural properties of Stevia rebaudiana leaves. JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2021; 101:6484-6495. [PMID: 34000065 DOI: 10.1002/jsfa.11320] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Revised: 04/12/2021] [Accepted: 05/17/2021] [Indexed: 06/12/2023]
Abstract
BACKGROUND Stevia leaves were subjected to convective hot-air, infrared and vacuum drying at 40, 60 and 80 °C, followed by an assessment of thermophysical properties and microstructure, along with drying kinetics modelling and evaluation of energy features for all drying operations. RESULTS Effective moisture diffusivity (Deff ) showed dependency on temperature with values ranging from 1.08 × 10-12 to 7.43 × 10-12 m2 s-1 for convective drying, from 0.71 × 10-12 to 6.60 × 10-12 m2 s-1 for infrared drying, and from 1.29 × 10-12 to 5.39 × 10-12 m2 s-1 for vacuum drying. The thermal properties of the dried Stevia leaves under different drying conditions showed values of density, specific heat, thermal diffusivity, thermal conductivity and thermal effusivity ranging from 95.6 to 116.2 kg m-3 , 3050 to 3900 J kg-1 K-1 , 4.28 × 10-7 to 5.60 × 10-7 m2 s-1 , 0.16 to 0.23 W m-1 K-1 and 244 to 305 W s0.5 m-2 K-1 , respectively. As for microstructure, convective hot-air drying showed better preserved leaf characteristics, compared to infrared- and vacuum-drying, whereby scanning electron microscopy (SEM) image analysis also revealed noticeable differences at higher temperatures. Statistical analysis showed that the Midilli-Kuçuk model fitted best the experimental data of drying curves (0.961 < r2 < 0.999, 0.000064 < SSE < 0.005359, and 0.000074 < χ2 < 0.006278). Comparison of the drying methods with respect to energy features showed that convective drying at 80 °C led to lowest specific energy consumption (61.86 kW h kg-1 ) with highest efficiency (8.5%). CONCLUSION The results of this study contribute to a better understanding of the drying behaviour and showed that thermophysical properties of dried Stevia leaves and energy features are affected by drying methods. © 2021 Society of Chemical Industry.
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Affiliation(s)
- Roberto Lemus-Mondaca
- Departamento de Ciencia de los Alimentos y Tecnología Química, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile
| | - Liliana Zura-Bravo
- Departamento de Ciencia de los Alimentos y Tecnología Química, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile
| | - Kong Ah-Hen
- Instituto de Ciencia y Tecnología de los Alimentos, Facultad de Ciencias Agrarias y Alimentarias, Universidad Austral de Chile, Valdivia, Chile
| | - Karina Di Scala
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
- Grupo de Investigación en Ingeniería en Alimentos, Facultad de Ingeniería, Universidad Nacional de Mar del Plata, Buenos Aires, Argentina
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Tuly SS, Mahiuddin M, Karim A. Mathematical modeling of nutritional, color, texture, and microbial activity changes in fruit and vegetables during drying: A critical review. Crit Rev Food Sci Nutr 2021; 63:1877-1900. [PMID: 34459302 DOI: 10.1080/10408398.2021.1969533] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Retention of quality attributes during drying of fruit and vegetables is a prime concern since the product's acceptability depends on the overall quality; particularly on the nutritional, color, and physical attributes. However, these quality parameters deteriorate during drying. Food quality changes are strongly related to the drying conditions and researchers have attempted to develop mathematical models to understand these relationships. A better insight toward the degradation of quality attributes is crucial for making real predictions and minimizing the quality deterioration. The previous empirical quality models employed kinetic modeling approaches to describe the quality changes and therefore, lack the realistic understanding of fundamental transport mechanisms. In order to develop a physics based mathematical model for the prediction of quality changes during drying, an in-depth understanding of research progress made toward this direction is indispensable. Therefore, the main goal of this paper is to present a critical review of the mathematical models developed and applied to describe the degradation kinetics of nutritional, color, and texture attributes during drying of fruit and vegetables and microbial growth model during storage. This review also presents the advantages and drawbacks of the existing models along with their industrial relevance. Finally, future research propositions toward developing physics-based mathematical model are presented.
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Affiliation(s)
- Sumaiya Sadika Tuly
- Faculty of Science and Engineering, Mechanical, Medical and Process Engineering, Queensland University of Technology, Brisbane, QLD, Australia
| | - Md Mahiuddin
- Faculty of Science and Engineering, Mechanical, Medical and Process Engineering, Queensland University of Technology, Brisbane, QLD, Australia
| | - Azharul Karim
- Faculty of Science and Engineering, Mechanical, Medical and Process Engineering, Queensland University of Technology, Brisbane, QLD, Australia
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Influence of Drying Type of Selected Fermented Vegetables Pomace on the Natural Colorants and Concentration of Lactic Acid Bacteria. APPLIED SCIENCES-BASEL 2021. [DOI: 10.3390/app11177864] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Nowadays, foods with probiotic bacteria are valuable and desired, because of their influence on human gut and health. Currently, in the era of zero waste, the food industry is interested in managing its waste. Therefore, the aim of the study was to determine the influence of drying process on the physicochemical properties of fermented vegetable pomace. The work included examining the influence of the lactic acid bacteria (Levilactobacillus brevis, Lactiplantibacillus plantarum, Limosilactobacillus fermentum and its mixture in the ratio 1:1:1) used for vegetable fermentation (beetroot, red pepper, carrot), obtaining pomace from fermented vegetables, and then selection of drying technique using the following methods: convection drying (CD) or freeze-drying (FD) on the physical and chemical properties of pomace. In the obtained pomace and its dried form, dry substance, water activity, color, and active substances such as betalains and carotenoids by spectrophotometric method and also bacteria concentration were evaluated. After fermentation of pomace from the same vegetable, a similar concentration of lactic acid bacteria was found as well as dry substances, color and colorants. Results of physico-chemical properties were related to the used vegetable type. After drying of pomace, it could be seen a high decrease in bacteria and colorant concentration (betalains, carotenoids) independently from drying and vegetable type as well as used starter cultures. The smallest change was observed for spontaneously fermented vegetables compared to those in which the starter culture was used.
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13
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Effect of drying methods on biorefinery process to obtain capsanthin and phenolic compounds from Capsicum annuum L. J Supercrit Fluids 2021. [DOI: 10.1016/j.supflu.2021.105241] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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14
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Martín-Diana AB, Tomé-Sánchez I, García-Casas MJ, Martínez-Villaluenga C, Frías J, Rico D. A Novel Strategy to Produce a Soluble and Bioactive Wheat Bran Ingredient Rich in Ferulic Acid. Antioxidants (Basel) 2021; 10:antiox10060969. [PMID: 34208721 PMCID: PMC8234745 DOI: 10.3390/antiox10060969] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Revised: 06/08/2021] [Accepted: 06/10/2021] [Indexed: 12/20/2022] Open
Abstract
Wheat bran (WB) is a byproduct from the milling industry that contains bioactive compounds beneficial to human health. The aim of this work was on the one hand, increasing extractability of antioxidant and anti-inflammatory compounds (specifically ferulic acid, FA), through enzymatic hydrolysis combined with hydrothermal treatment (HT) and high hydrostatic pressure (HHP). On the other hand, enhancing the stability of final ingredient applying spray-drying (SPD) and microencapsulation (MEC). The use of HT increased FA, total phenolics (TP), and antioxidant capacity (AC) in WB hydrolysates, regardless the HT duration. However, the HT tested (30 min, HT30) produced a loss in anti-inflammatory activity (AIA). The combination of HT (15 min, HT15) with HHP increased AIA of the WB. SPD enhanced the TP yield in WB with no significant effect of inlet temperature (up to 140 °C) on phenolic profile mainly composed of trans-FA and smaller amounts of cis-FA and apigenin diglucosides. SPD caused a temperature-dependent increase in AC (160 °C > 140 °C > 130 °C). SPD inlet temperatures affected total solids yield (from 22 to 36%), with the highest values at 140 °C. The use of HHP in combination with HT resulted in >2-fold increase in total solids yield.
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Affiliation(s)
- Ana Belén Martín-Diana
- Agricultural Technological Institute of Castile and Leon (ITACyL), Government of Castile and Leon, Ctra. de Burgos Km. 119, Finca Zamadueñas, 47071 Valladolid, Spain; (M.J.G.-C.); (D.R.)
- Correspondence: ; Tel.: +34-983-41-0366
| | - Irene Tomé-Sánchez
- Institute of Food Science, Technology and Nutrition (ICTAN-CSIC), José Antonio Novais 10, 28040 Madrid, Spain; (I.T.-S.); (C.M.-V.); (J.F.)
| | - María Jesús García-Casas
- Agricultural Technological Institute of Castile and Leon (ITACyL), Government of Castile and Leon, Ctra. de Burgos Km. 119, Finca Zamadueñas, 47071 Valladolid, Spain; (M.J.G.-C.); (D.R.)
| | - Cristina Martínez-Villaluenga
- Institute of Food Science, Technology and Nutrition (ICTAN-CSIC), José Antonio Novais 10, 28040 Madrid, Spain; (I.T.-S.); (C.M.-V.); (J.F.)
| | - Juana Frías
- Institute of Food Science, Technology and Nutrition (ICTAN-CSIC), José Antonio Novais 10, 28040 Madrid, Spain; (I.T.-S.); (C.M.-V.); (J.F.)
| | - Daniel Rico
- Agricultural Technological Institute of Castile and Leon (ITACyL), Government of Castile and Leon, Ctra. de Burgos Km. 119, Finca Zamadueñas, 47071 Valladolid, Spain; (M.J.G.-C.); (D.R.)
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Kolla MC, Laya A, Bayang JP, Koubala BB. Effect of different drying methods and storage conditions on physical, nutritional, bioactive compounds and antioxidant properties of doum ( Hyphaene thebaica) fruits. Heliyon 2021; 7:e06678. [PMID: 33889782 PMCID: PMC8050005 DOI: 10.1016/j.heliyon.2021.e06678] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Revised: 11/23/2020] [Accepted: 03/29/2021] [Indexed: 01/12/2023] Open
Abstract
The present study reports effect of various drying and storage conditions on physical, bioactive compounds, and antioxidant properties of doum (H. thebaica) fruit for the first time. Three types of fruit are used such as fresh, dried from tree, and dried fruits purchased from local market. Pulp of fresh fruit was dried using sun, shade and oven at different temperatures and stored under different conditions for three months. Samples were analysed before and after drying and storage. The results showed significantly (p < 0.01) higher dry matter (98.73 g/100g), pH (7.09), tannins (27.64 mg/g), flavonoids (19.90 mg/g) and total polyphenols (7.13 mg/g) contents in pericarp than other parts of fruit. The pulp without pericarp exhibited higher ash, amino acids, proteins and vitamin C contents, however pulp of whole fresh fruit had higher Ca (1.67 mg/g), Na (640.26 mg/g) and Zn (11.63 μg/g). Pulp of fruit purchased from local market showed significantly stronger antioxidant activities (DPPH and ABTS). All parameters evaluated were significantly (p < 0.01) affected in comparison with pulp of fresh fruit but varied with respect to drying methods and storage conditions. The shade-dried samples showed higher proteins, amino acids, vitamin C, ash, fibres and acidity contents than other drying methods. Polyphenols and antioxidant activities are higher in oven-dried samples at low temperature (40 °C) as compared to others. The highest DPPH and ABTS scavenging activities are observed after drying and storage conditions for three months. Significant and positive (p < 0.01) correlations are found between antioxidant compounds and antioxidant activities. Thus, drying methods and storage conditions can preserve pulp of doum fruit with high physicochemical, bioactive compounds and antioxidant capacities for human well-being up to three months, however shade-drying followed by oven-drying are highly promising process that must be considered as suitable drying methods for doum fruits.
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Affiliation(s)
- M C Kolla
- Department of Biological Sciences, Faculty of Science, University of Maroua, P.O. Box 46, Maroua, Cameroon
| | - A Laya
- Department of Biological Sciences, Faculty of Science, University of Maroua, P.O. Box 46, Maroua, Cameroon.,Department of Life and Earth Sciences, Higher Teacher's Training College of Maroua, University of Maroua, P.O. Box 55, Maroua, Cameroon
| | - J P Bayang
- Department of Biological Sciences, Faculty of Science, University of Maroua, P.O. Box 46, Maroua, Cameroon
| | - B B Koubala
- Department of Chemistry, Faculty of Science, University of Maroua, P.O. Box 814, Maroua, Cameroon.,Department of Life and Earth Sciences, Higher Teacher's Training College of Maroua, University of Maroua, P.O. Box 55, Maroua, Cameroon
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Pervin S, Aziz MG, Miaruddin M. Kinetics of dehydration and appreciation of the physicochemical properties of osmo-dehydrated plum. Food Sci Nutr 2021; 9:2203-2216. [PMID: 33841836 PMCID: PMC8020930 DOI: 10.1002/fsn3.2191] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2020] [Revised: 01/14/2021] [Accepted: 02/08/2021] [Indexed: 11/21/2022] Open
Abstract
The experiment was conducted to evaluate the dehydration kinetics and quantify its effect on the various physicochemical properties of the osmo-dehydrated plum during storage at an ambient condition. The six treatments with a combination of three different sucrose-sodium chloride concentrations and two peeling conditions were selected in the experiment. Among the treatments, peeled plum dipped into 5% NaCl solution exhibited a faster drying rate. Concerning the rehydration properties of the osmo-dehydrated plum, the whole plum immersed into 500B sucrose solution showed the highest reconstitution behavior and the lowest moisture content (wb). The highest values of water activity of 0.514 and the lowest values of texture 1.79 N-mm2 were investigated in 500B sucrose treated whole plum. The peeled plum obtained the highest lightness (L), redness (a*), and yellowness (b*) compared to the unpeeled plum. Osmo-dehydrated plum with high sugar solution contained more sugar and less total phenolic content nevertheless using only 5% NaCl resulted in less sugar and more total phenolic content after the treatment. The osmo-dehydrated whole plums prepared in 500B sucrose scored the highest overall acceptability (8.0, e.g., like very much) followed by the 500B sucrose with peeled plum envisaged the sensory evaluation analysis. In conclusion, the osmo-dehydrated plum treated in 500B sucrose and unpeeled condition performed better with a view to the overall plum quality, color, and acceptability judged by the expert panelists even after 12 months of storage at room temperature.
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Affiliation(s)
- Shahnaj Pervin
- Department of Food Technology and Rural IndustriesBangladesh Agricultural UniversityMymensinghBangladesh
- Postharvest Technology DivisionBangladesh Agricultural Research InstituteGazipurBangladesh
| | - Md. Gulzarul Aziz
- Department of Food Technology and Rural IndustriesBangladesh Agricultural UniversityMymensinghBangladesh
| | - Md. Miaruddin
- Postharvest Technology DivisionBangladesh Agricultural Research InstituteGazipurBangladesh
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Artichoke by Products as a Source of Antioxidant and Fiber: How It Can Be Affected by Drying Temperature. Foods 2021; 10:foods10020459. [PMID: 33669757 PMCID: PMC7922872 DOI: 10.3390/foods10020459] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 02/12/2021] [Accepted: 02/16/2021] [Indexed: 11/17/2022] Open
Abstract
The reuse of food industry by-products constitutes one of the essential pillars of the change from a linear to a circular economic model. Drying is one of the most affordable techniques with which to stabilize by-products, making their subsequent processing possible. However, it can affect material properties. The objective of this study was to assess the effect of the drying temperature on the drying kinetics and final quality of the main artichoke processing by-products, bracts and stems, which have never been studied as independent materials. For this purpose, air drying experiments at different temperatures (40, 60, 80, 100 and 120 °C) were carried out. The alcohol insoluble residue (AIR) and the total phenolic content (TPC), antioxidant capacity (AC) and vitamin C (VC) of the fresh and dried samples were determined. The bracts dried faster than the stems, increasing drying rate with temperature. The two by-products presented relatively large amounts of AIR, the content being higher in bracts, but better functional properties in stems. The TPC, AC and VC values of the dried samples decreased in relation to the fresh samples, with the temperatures of 40 °C (bracts) and 120 °C (stems) being the most adequate for the purposes of preserving these characteristics.
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18
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Hussein JB, Oke MO, Abiona OO, Adebayo Q. Optimization of processing parameters for drying of tomatoes (
Solanum lycopersicum
L.var) slices using Taguchi technique. J FOOD PROCESS PRES 2020. [DOI: 10.1111/jfpp.15149] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Jelili B. Hussein
- Department of Food Science and Technology Modibbo Adama University of Technology Yola Nigeria
| | - Moruf O. Oke
- Department of Food Engineering Ladoke Akintola University of Technology Ogbomoso Nigeria
| | - Oluseye O. Abiona
- Department of Chemical Sciences Osun State University Osogbo Nigeria
| | - Quadri Adebayo
- Department of Food Science and Technology Federal University Dutsinma Nigeria
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19
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Marzec A, Kowalska H, Kowalska J, Domian E, Lenart A. Influence of Pear Variety and Drying Methods on the Quality of Dried Fruit. MOLECULES (BASEL, SWITZERLAND) 2020; 25:molecules25215146. [PMID: 33167405 PMCID: PMC7663804 DOI: 10.3390/molecules25215146] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/13/2020] [Revised: 10/29/2020] [Accepted: 11/03/2020] [Indexed: 01/13/2023]
Abstract
In this study, the impacts of two different pear cultivars, “Conference” and “Alexander Lucas”, on the kinetics and the final quality of samples dried by convection (CD) and microwave-convection (MCD) methods, were investigated. The quality of dried material was evaluated by the analysis of water activity, porosity, color, acoustic emission (AE) and mechanical and sensory properties. The required drying time to obtain 0.2 kg H2O/kg dry solid (d.s.) was longer for “Conference” than “Alexander Lucas” and was 20 min by CD and 5 min by MCD. The pear cultivar, in conjunction with the drying method (CD or MCD), affected the number of AE events and the work of breaking. The CD pear of the “Conference” cultivar was characterized by higher force, higher breaking work and stronger AE relative to the CD pear of the “Alexander Lucas” cultivar. There were no differences in taste or overall quality, but the hardness was higher for the CD “Conference” pear. A principal component analysis showed that panelists preferred dried fruit with good taste and overall quality but lower hardness. A positive correlation was found between the number of acoustic events and sensory hardness; thus, an acoustic method can be useful for effectively evaluating the texture of dried pears. These results show that the dried pear slices that generated fewer AE events upon breaking were perceived as better by the panelists.
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Affiliation(s)
- Agata Marzec
- Department of Food Engineering and Process Management, Institute of Food Science, Warsaw University of Life Sciences—SGGW, 159c Nowoursynowska St., 02-776 Warsaw, Poland; (H.K.); (E.D.); (A.L.)
- Correspondence: ; Tel.: +48-22-593-75-65; Fax: +48-22-593-75-76
| | - Hanna Kowalska
- Department of Food Engineering and Process Management, Institute of Food Science, Warsaw University of Life Sciences—SGGW, 159c Nowoursynowska St., 02-776 Warsaw, Poland; (H.K.); (E.D.); (A.L.)
| | - Jolanta Kowalska
- Division of Food Quality Evaluation, Institute of Food Science, Warsaw University of Life Sciences—SGGW, 159c Nowoursynowska St., 02-776 Warsaw, Poland;
| | - Ewa Domian
- Department of Food Engineering and Process Management, Institute of Food Science, Warsaw University of Life Sciences—SGGW, 159c Nowoursynowska St., 02-776 Warsaw, Poland; (H.K.); (E.D.); (A.L.)
| | - Andrzej Lenart
- Department of Food Engineering and Process Management, Institute of Food Science, Warsaw University of Life Sciences—SGGW, 159c Nowoursynowska St., 02-776 Warsaw, Poland; (H.K.); (E.D.); (A.L.)
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20
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Coradi PC, Dubal ÍTP, Bilhalva NDS, Fontoura CN, Teodoro PE. Correlation using multivariate analysis and control of drying and storage conditions of sunflower grains on the quality of the extracted vegetable oil. J FOOD PROCESS PRES 2020. [DOI: 10.1111/jfpp.14961] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Paulo Carteri Coradi
- Campus Cachoeira do Sul Federal University of Santa Maria Cachoeira do Sul Brazil
- Department of Agricultural Engineering Federal University of Santa Maria Santa Maria Brazil
- Campus de Chapadão do Sul Federal University of Mato Grosso do Sul Chapadão do Sul Brazil
| | | | | | - Camila Nunes Fontoura
- Department of Agricultural Engineering Federal University of Santa Maria Santa Maria Brazil
| | - Paulo Eduardo Teodoro
- Campus de Chapadão do Sul Federal University of Mato Grosso do Sul Chapadão do Sul Brazil
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Agbede OO, Oke EO, Akinfenwa SI, Wahab KT, Ogundipe S, Aworanti OA, Arinkoola AO, Agarry SE, Ogunleye OO, Osuolale FN, Babatunde KA. Thin layer drying of green microalgae (Chlorella sp.) paste biomass: Drying characteristics, energy requirement and mathematical modeling. ACTA ACUST UNITED AC 2020. [DOI: 10.1016/j.biteb.2020.100467] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Fernández-López JA, Fernández-Lledó V, Angosto JM. New insights into red plant pigments: more than just natural colorants. RSC Adv 2020; 10:24669-24682. [PMID: 35516216 PMCID: PMC9055186 DOI: 10.1039/d0ra03514a] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2020] [Accepted: 06/16/2020] [Indexed: 12/02/2022] Open
Abstract
Pigments make nature both colorful and attractive. Humans have always incorporated the natural pigments of fruits, vegetables and spices into their dietary requirements. Naturally occurring red pigments in plants are carotenoids, anthocyanins and betacyanins. Natural pigments, apart from colour, provide added properties and are therefore considered to be bioactive constituents. Red natural colorants are one of the most widely used in the food industry. The interest in these pigments lies in the enhancement of the healthy effects of the diet. In this context, attention is given to carotenoids, anthocyanins and betacyanins, with emphasis on the basic chemical and biochemical attributes and wide-ranging health-promoting benefits of these pigments. Thus, in this review, we systematically present the advantages and limitations of these natural pigments as food colorants in relation to their physico-chemical properties, reactivity and bioactivity.
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Affiliation(s)
- José A Fernández-López
- Department of Chemical and Environmental Engineering, Technical University of Cartagena (UPCT) Paseo Alfonso XIII 52 E-30203 Cartagena Murcia Spain
| | - Vicente Fernández-Lledó
- Higher Technical School of Telecommunications, Technical University of Madrid (UPM) Madrid Spain
| | - José M Angosto
- Department of Chemical and Environmental Engineering, Technical University of Cartagena (UPCT) Paseo Alfonso XIII 52 E-30203 Cartagena Murcia Spain
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24
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Equilibrium Moisture and Drying Kinetics Modelling of Macroalgae Species Ulva ohnoi and Oedogonium intermedium. CLEAN TECHNOLOGIES 2020. [DOI: 10.3390/cleantechnol2020015] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Algae-based products have applications in the food and pharmaceutical industries, bioremediation of waste streams and biofuel production. Drying has been recognised to constitute the largest energy cost in algae processing, yet there is limited data or modelling characterising the drying kinetics of macroalgae. This research modelled the equilibrium moisture content of two macroalgae species, Ulva ohnoi, a saltwater alga and Oedogonium intermedium, a freshwater alga. The Guggenheim–Anderson–de Boer model was found to best represent experimental equilibrium moisture contents. Drying rate curves obtained under both convective and radiative conditions were fitted to an analytical solution of Fick’s second law, including the modelled equilibrium moisture values. Effective diffusivity values for the two species are presented.
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25
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Çalışkan Koç G. The effect of different drying techniques and microwave finish drying on the powder properties of the red pepper powder ( Capsicum annuum L.). Journal of Food Science and Technology 2020; 57:4576-4587. [PMID: 33087970 DOI: 10.1007/s13197-020-04496-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Revised: 04/09/2020] [Accepted: 04/29/2020] [Indexed: 10/24/2022]
Abstract
The objective of this study was to investigate the effects of different drying processes (microwave, freeze, convective hot air, and vacuum drying) and microwave finish drying (FD + MD and CD + MD) on the physical and powder properties of the red pepper powder. The effect of moisture content on the powder properties and the relationship between microwave output power or drying temperature and physical and powder properties were also determined by using most common mathematical models (linear, power, logarithmic, and quadratic). Results showed that an increase in both microwave output power and temperature (for CD and VD) generally resulted in a decrease in drying time, moisture content, and chroma and an increase in bulk and tapped density values. The drying time, moisture content, and water activity values can be significantly decreased, whereas, the color values can be significantly increased by combining FD and CD with microwave finish drying (P < 0.05). The moisture content (y = - 1.94 ln(x) + 7.6455, R2 = 0.9905), bulk (y = 54.224 ln(x) + 153.71, R2 = 0.9705), tapped (y = 61.7 ln(x) + 225.6, R2 = 0.9994) and particle densities (y = - 327.4 ln(x) + 2260.5, R2 = 0.9966), and porosity (y = - 3.778 ln(x) + 89.806, R2 = 0.9586) values followed a logarithmic trend depending on the increase in the convective hot air drying temperature. The inverse relationship was observed between the moisture content, bulk and tapped densities of the red pepper powders.
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Khodja YK, Dahmoune F, Bachir bey M, Madani K, Khettal B. Conventional method and microwave drying kinetics of Laurus nobilis leaves: effects on phenolic compounds and antioxidant activity. BRAZILIAN JOURNAL OF FOOD TECHNOLOGY 2020. [DOI: 10.1590/1981-6723.21419] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Abstract Laurus nobilis constitutes one of the usually studied Mediterranean trees due to its therapeutic effects, nutritional properties, and ornamental use. In the current investigation, a comparative study was conducted between two types of drying methods, a microwave-assisted drying (MWD) (from 180 to 900 W) and a conventional method (open-air and oven-drying using temperatures from 40 °C to 120 °C). Drying kinetics were carried out as a function of moisture content according to time. Total Phenolic Content (TPC) as well as reducing power of obtained products were determined. Kinetic results showed that the time required for dried bay leaves became shorter as temperature and microwave power increased; drying with the microwave was much more efficient than conventional methods (open-air and oven-drying). Antioxidants of the Laurus nobilis leaves were better conserved using open-air and microwave drying. Our results underlined a significant correlation between TPC and reducing power. Microwave drying using 300 W during 130 s was the most efficient combination that provided dried bay leaves with the highest content of phenolic compounds and antioxidant activity.
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Affiliation(s)
| | - Farid Dahmoune
- Faculté des Sciences de la Nature et de la Vie, Biophysique, Biochimie et Scientométrie, Algeria
| | | | - Khodir Madani
- Faculté des Sciences de la Nature et de la Vie, Biophysique, Biochimie et Scientométrie, Algeria
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28
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Hwang MJ, Kang SJ, Kim HS, Lee KW. Reduction of the polycyclic aromatic hydrocarbon levels in dried red peppers (Capsicum annuum L.) using heat pump-assisted drying. Food Chem 2019; 297:124977. [DOI: 10.1016/j.foodchem.2019.124977] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2018] [Revised: 05/13/2019] [Accepted: 06/10/2019] [Indexed: 11/15/2022]
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29
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Sanatombi K, Rajkumari S. Effect of Processing on Quality of Pepper: A Review. FOOD REVIEWS INTERNATIONAL 2019. [DOI: 10.1080/87559129.2019.1669161] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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30
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Xanthopoulos G, Athanasiou A, Sempou A, Lentzou D, Templalexis C, Boudouvis A. Study of the Drying Rate and Colour Kinetics during Stepwise Air-Drying of Apricot Halves. INTERNATIONAL JOURNAL OF FOOD ENGINEERING 2019. [DOI: 10.1515/ijfe-2018-0372] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
AbstractThe drying rate and colour kinetics of apricot halves were studied during stepwise air-drying compared to continuous drying. The tested stepwise temperature profiles exhibited two successive falling rate periods, which differed from the drying rate period of the constant drying temperature profile. Three chromatic indices, namely browning index, chroma and hue were analysed. The analysis showed that treatment with ascorbic acid was more effective during the step up temperature profile, whilst its antioxidant activity was lost during the step down temperature profile due to the initially used high drying temperatures. The chromatic indices were described by a modified kinetic model, the parameters of which were estimated by the Levenberg–Marquardt optimization algorithm and in all cases was derived R2adj≥ 0.88 and MRD < 4.88%.
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Affiliation(s)
- G. Xanthopoulos
- Department of Natural Resources Management and Agricultural Engineering, Agricultural University of Athens, 75 Iera Odos Str., Athens, 11855, Greece
| | - A. Athanasiou
- Department of Natural Resources Management and Agricultural Engineering, Agricultural University of Athens, 75 Iera Odos Str., Athens, 11855, Greece
| | - A. Sempou
- School of Chemical Engineering, National Technical University of Athens, 9 Heroon Polytechniou Str., Zografou, 15780, Greece
| | - D. Lentzou
- Department of Natural Resources Management and Agricultural Engineering, Agricultural University of Athens, 75 Iera Odos Str., Athens, 11855, Greece
| | - Ch. Templalexis
- Department of Natural Resources Management and Agricultural Engineering, Agricultural University of Athens, 75 Iera Odos Str., Athens, 11855, Greece
| | - A.G. Boudouvis
- School of Chemical Engineering, National Technical University of Athens, 9 Heroon Polytechniou Str., Zografou, 15780, Greece
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31
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Modeling Degradation Kinetics in Dry Foods Storage under Varying Temperature and Moisture Content—Theoretical Evaluation. FOOD ENGINEERING REVIEWS 2019. [DOI: 10.1007/s12393-018-9185-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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32
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Nallan Chakravartula SS, Cevoli C, Balestra F, Fabbri A, Dalla Rosa M. Evaluation of drying of edible coating on bread using NIR spectroscopy. J FOOD ENG 2019. [DOI: 10.1016/j.jfoodeng.2018.07.009] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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33
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Rahman NFA, Shamsudin R, Ismail A, Shah NNAK, Varith J. Effects of drying methods on total phenolic contents and antioxidant capacity of the pomelo (Citrus grandis (L.) Osbeck) peels. INNOV FOOD SCI EMERG 2018. [DOI: 10.1016/j.ifset.2018.01.009] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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34
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Khaldi Y, Tounsi L, Balti MA, Kechaou N. Impact of microwave drying on sesame coats quality. J FOOD PROCESS ENG 2018. [DOI: 10.1111/jfpe.12860] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Yakouta Khaldi
- Research Group of Agri-Food Processing Engineering, Laboratory of Applied Fluids Mechanics, Process Engineering and Environment; National School of Engineers of Sfax, University of Sfax; Sfax Tunisia
| | - Leila Tounsi
- Research Group of Agri-Food Processing Engineering, Laboratory of Applied Fluids Mechanics, Process Engineering and Environment; National School of Engineers of Sfax, University of Sfax; Sfax Tunisia
| | - Mohamed Amine Balti
- Research Group of Agri-Food Processing Engineering, Laboratory of Applied Fluids Mechanics, Process Engineering and Environment; National School of Engineers of Sfax, University of Sfax; Sfax Tunisia
| | - Nabil Kechaou
- Research Group of Agri-Food Processing Engineering, Laboratory of Applied Fluids Mechanics, Process Engineering and Environment; National School of Engineers of Sfax, University of Sfax; Sfax Tunisia
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35
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Kumari P, Khatkar BS. Nutritional composition and drying kinetics of aonla fruits. JOURNAL OF FOOD SCIENCE AND TECHNOLOGY 2018; 55:3135-3143. [PMID: 30065424 DOI: 10.1007/s13197-018-3241-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Revised: 05/15/2018] [Accepted: 05/21/2018] [Indexed: 11/24/2022]
Abstract
Drying kinetics and effects of drying on nutritional properties of 5 varieties of aonla were investigated using cabinet dryer. Thin shreds of aonla were spread in a layer in dryer and dried at varying temperature of 40, 50 and 60 °C till constant weight attained. Thin layer Newton model was proposed to study drying kinetic of aonla varieties. Degradation in TPC (total phenolic content) and ascorbic acid content were studied at varying temperature. Total phenolic and ascorbic acid content were retained maximum at 50 °C and higher values of R2 and the lowest value of root mean square error (RMSE), Chi square and mean biased error (MBE) for all varieties indicated that Newton model appropriately described the drying curve of aonla. Among the varieties, variety Banarasi had maximum value of R2 (0.993) and the lowest values for RMSE (0.039), Chi square (0.018) and MBE (0.001) at 50 °C. Reduction was observed in ascorbic acid, reducing sugar, polyphenol content and pectin content of aonla varieties during drying process. From study, it was observed that drying of aonla at 50 °C was best in terms of higher retention of TPC and ascorbic acid and Newton model was found suitable to explain drying pattern within temperature range under study.
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Affiliation(s)
- Parveen Kumari
- Department of Food Technology, Guru Jambheshwar University of Science and Technology, Hisar, 125001 India
| | - B S Khatkar
- Department of Food Technology, Guru Jambheshwar University of Science and Technology, Hisar, 125001 India
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37
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Wheat germ thermal treatment in fluidised bed. Experimental study and mathematical modelling of the heat and mass transfer. J FOOD ENG 2018. [DOI: 10.1016/j.jfoodeng.2017.09.029] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Convective Drying of Osmo-Treated Abalone (Haliotis rufescens) Slices: Diffusion, Modeling, and Quality Features. J FOOD QUALITY 2018. [DOI: 10.1155/2018/6317943] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
The focus of this research was based on the application of an osmotic pretreatment (15% NaCl) for drying abalone slices, and it evaluates the influence of hot-air drying temperature (40–80°C) on the product quality. In addition, the mass transfer kinetics of salt and water was also studied. The optimal time of the osmotic treatment was established until reaching a pseudo equilibrium state of the water and salt content (290 min). The water effective diffusivity values during drying ranged from 3.76 to 4.75 × 10−9 m2/s for three selected temperatures (40, 60, and 80°C). In addition, experimental data were fitted by Weibull distribution model. The modified Weibull model provided good fitting of experimental data according to applied statistical tests. Regarding the evaluated quality parameters, the color of the surface showed a change more significant at high temperature (80°C), whereas the nonenzymatic browning and texture showed a decrease during drying process mainly due to changes in protein matrix and rehydration rates, respectively. In particular, working at 60°C resulted in dried samples with the highest quality parameters.
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39
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Liu W, Zhao Y, Sun J, Li G, Shan Y, Chen P. Study the effects of drying processes on chemical compositions in daylily flowers using flow injection mass spectrometric fingerprinting method and chemometrics. Food Res Int 2017; 102:493-503. [DOI: 10.1016/j.foodres.2017.09.015] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Revised: 09/05/2017] [Accepted: 09/08/2017] [Indexed: 11/26/2022]
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40
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Duc Pham N, Khan MIH, Joardder MUH, Rahman MM, Mahiuddin M, Abesinghe AN, Karim MA. Quality of plant-based food materials and its prediction during intermittent drying. Crit Rev Food Sci Nutr 2017; 59:1197-1211. [DOI: 10.1080/10408398.2017.1399103] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- Nghia Duc Pham
- Science and Engineering Faculty, Queensland University of Technology, 2 George Street, Brisbane, QLD 4001, Australia
- Engineering Faculty, Vietnam National University of Agriculture, Vietnam
| | - Md Imran H. Khan
- Science and Engineering Faculty, Queensland University of Technology, 2 George Street, Brisbane, QLD 4001, Australia
- Department of Mechanical Engineering, Dhaka University of Engineering & Technology, Gazipur 1700, Bangladesh
| | - M U H Joardder
- Science and Engineering Faculty, Queensland University of Technology, 2 George Street, Brisbane, QLD 4001, Australia
| | - M. M. Rahman
- Science and Engineering Faculty, Queensland University of Technology, 2 George Street, Brisbane, QLD 4001, Australia
| | - Md. Mahiuddin
- Science and Engineering Faculty, Queensland University of Technology, 2 George Street, Brisbane, QLD 4001, Australia
- Department of Mechanical Engineering, Dhaka University of Engineering & Technology, Gazipur 1700, Bangladesh
| | - A.M. Nishani Abesinghe
- Science and Engineering Faculty, Queensland University of Technology, 2 George Street, Brisbane, QLD 4001, Australia
| | - M. A. Karim
- Science and Engineering Faculty, Queensland University of Technology, 2 George Street, Brisbane, QLD 4001, Australia
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41
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Jiang G, Nam S, Eun J. Effects of peeling, drying temperature, and sodium metabisulfite treatment on physicochemical characteristics and antioxidant activities of Asian pear powders. J FOOD PROCESS PRES 2017. [DOI: 10.1111/jfpp.13526] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Gui‐Hun Jiang
- Department of Food Science and Technology and BK 21 Plus ProgramGraduate School of Chonnam National UniversityGwangju 61186 South Korea
| | - Seung‐Hee Nam
- Department of Food Science and Technology and BK 21 Plus ProgramGraduate School of Chonnam National UniversityGwangju 61186 South Korea
- Institute of Agricultural Science and Technology and Department of Food Science & TechnologyChonnam National UniversityGwangju 61186 South Korea
| | - Jong‐Bang Eun
- Department of Food Science and Technology and BK 21 Plus ProgramGraduate School of Chonnam National UniversityGwangju 61186 South Korea
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42
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Quality Assessment and Mathematical Modeling of Hot-Air Convective Drying of Persimmon (Diospyros kaki L.) Fruit. INTERNATIONAL JOURNAL OF FOOD ENGINEERING 2017. [DOI: 10.1515/ijfe-2016-0333] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
The influence of drying on the color, porosity, shrinkage and moisture of persimmon fruit during convective drying was determined by computer vision. The experiments were performed with persimmon fruit that were cut into slab 20 × 20 mm, which were arranged into a bigger slab, 60 × 60 mm. Drying process was carried out at 60 °C. Noticeable changes in quality parameters (color, porosity and shrinkage) could be observed during the drying process, where the central region of the sample evidenced less changes. Persimmon’s physical properties were experimentally obtained as the temperature function and heat and mass convective coefficients were adjusted as a time function. A numerical simulation using the Finite Volume Method allowed to describe the evolution of temperature and moisture content distributions during drying. The numerical and experimental results of temperature and moisture during persimmon drying were found to be in a good agreement.
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43
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Saavedra J, Córdova A, Navarro R, Díaz-Calderón P, Fuentealba C, Astudillo-Castro C, Toledo L, Enrione J, Galvez L. Industrial avocado waste: Functional compounds preservation by convective drying process. J FOOD ENG 2017. [DOI: 10.1016/j.jfoodeng.2016.11.018] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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44
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López J, Vega-Gálvez A, Rodríguez A, Uribe E, Díaz P. Vacuum drying of Chilean murta (Ugni molinaeTurcz) berries: Effect of temperature on kinetic parameters and assessment of energy consumption. J FOOD PROCESS PRES 2016. [DOI: 10.1111/jfpp.13162] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Jéssica López
- Department of Food Engineering, Facultad de Ingeniería; Universidad de La Serena; La Serena Chile
| | - Antonio Vega-Gálvez
- Department of Food Engineering, Facultad de Ingeniería; Universidad de La Serena; La Serena Chile
| | - Angela Rodríguez
- Department of Food Engineering, Facultad de Ingeniería; Universidad de La Serena; La Serena Chile
| | - Elsa Uribe
- Department of Food Engineering, Facultad de Ingeniería; Universidad de La Serena; La Serena Chile
| | - Pilar Díaz
- Department of Food Engineering, Facultad de Ingeniería; Universidad de La Serena; La Serena Chile
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45
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Fratianni A, Niro S, Messia MC, Cinquanta L, Panfili G, Albanese D, Di Matteo M. Kinetics of carotenoids degradation and furosine formation in dried apricots (Prunus armeniaca L.). Food Res Int 2016; 99:862-867. [PMID: 28847423 DOI: 10.1016/j.foodres.2016.12.009] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Revised: 12/16/2016] [Accepted: 12/19/2016] [Indexed: 10/20/2022]
Abstract
The kinetics of carotenoid and color degradation, as well as furosine formation, were investigated in apricot fruits during convective heating at 50, 60 and 70°C. Degradation of carotenoids and color, expressed as total color difference (TCD), followed a first and zero order kinetic, respectively. The activation energy (Ea) for carotenoids degradation ranged from 73.7kJ/mol for 13-cis-β-carotene to 120.7kJ/mol for lutein, being about 91kJ/mol for all-trans-β-carotene. Violaxanthin and anteraxanthin were the most susceptible to thermal treatment. The furosine evolution was fitted at zero order kinetic model. The Ea for furosine formation was found to be 83.3kJ/mol and the Q10 (temperature coefficient) varied from 1.59 to 4.14 at the temperature ranges 50-60°C and 60-70°C, respectively.
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Affiliation(s)
- A Fratianni
- Dipartimento di Agricoltura, Ambiente e Alimenti, Università degli Studi del Molise, Via De Sanctis, 86100 Campobasso, Italy
| | - S Niro
- Dipartimento di Agricoltura, Ambiente e Alimenti, Università degli Studi del Molise, Via De Sanctis, 86100 Campobasso, Italy
| | - M C Messia
- Dipartimento di Agricoltura, Ambiente e Alimenti, Università degli Studi del Molise, Via De Sanctis, 86100 Campobasso, Italy
| | - L Cinquanta
- Dipartimento di Agricoltura, Ambiente e Alimenti, Università degli Studi del Molise, Via De Sanctis, 86100 Campobasso, Italy.
| | - G Panfili
- Dipartimento di Agricoltura, Ambiente e Alimenti, Università degli Studi del Molise, Via De Sanctis, 86100 Campobasso, Italy
| | - D Albanese
- Dipartimento Ingegneria Industriale, Università di Salerno, Via Ponte Don Melillo, 84084 Fisciano, SA, Italy
| | - M Di Matteo
- Dipartimento Ingegneria Industriale, Università di Salerno, Via Ponte Don Melillo, 84084 Fisciano, SA, Italy
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46
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Jablonski JE, Johnson MT, Keller SE. Hydrophilic interaction liquid chromatography-mass spectrometry for cinnamic acid determination and its use to evaluate components of dried hot peppers (Capsicum annum
) associated with growth inhibition of Salmonella enterica
serovars. J Food Biochem 2016. [DOI: 10.1111/jfbc.12342] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Joseph E. Jablonski
- U. S. Food and Drug Administration; Center for Food Safety and Applied Nutrition; Bedford Park IL USA
| | - Mary Teena Johnson
- Institute for Food Safety and Health Illinois Institute of Technology; Chicago IL USA
| | - Susanne E. Keller
- U. S. Food and Drug Administration; Center for Food Safety and Applied Nutrition; Bedford Park IL USA
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47
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Cao ZZ, Zhou LY, Bi JF, Yi JY, Chen QQ, Wu XY, Zheng JK, Li SR. Effect of different drying technologies on drying characteristics and quality of red pepper (Capsicum frutescens L.): a comparative study. JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2016; 96:3596-3603. [PMID: 26612038 DOI: 10.1002/jsfa.7549] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2015] [Revised: 11/15/2015] [Accepted: 11/15/2015] [Indexed: 06/05/2023]
Abstract
BACKGROUND Hot air drying and sun drying are traditional drying technologies widely used in the drying of agricultural products for a long time, but usually recognized as time-consuming or producing lower-quality products. Infrared drying is a rather effective drying technology that has advantages over traditional drying technologies. Thus, in order to investigate the application of infrared drying in the dehydration of red pepper, the drying characteristics and quality of infrared-dried red pepper were compared with those of sun-dried and hot air-dried red pepper. RESULTS The infrared drying technology significantly enhanced the drying rate when compared with hot air drying and sun drying. Temperature was the most important factor affecting the moisture transfer during the process of infrared drying as well as hot air drying. Effective moisture diffusivity (Deff ) values of infrared drying ranged from 1.58 × 10(-9) to 3.78 × 10(-9) m(2) s(-1) . The Ea values of infrared drying and hot air drying were 42.67 and 44.48 kJ mol(-1) respectively. Infrared drying and hot air drying produced color loss to a similar extent. Relatively higher crispness values were observed for infrared-dried samples. CONCLUSION Sun drying produced dried red pepper with the best color when compared with hot air drying and infrared drying. Meanwhile, infrared drying markedly improved the drying rate at the same drying temperature level of hot air drying, and the products obtained had relatively better quality with higher crispness values. © 2015 Society of Chemical Industry.
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Affiliation(s)
- Zhen-Zhen Cao
- Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences/Key Laboratory of Agro-products Processing, Ministry of Agriculture, Beijing 100193, China
| | - Lin-Yan Zhou
- Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences/Key Laboratory of Agro-products Processing, Ministry of Agriculture, Beijing 100193, China
| | - Jin-Feng Bi
- Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences/Key Laboratory of Agro-products Processing, Ministry of Agriculture, Beijing 100193, China
| | - Jian-Yong Yi
- Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences/Key Laboratory of Agro-products Processing, Ministry of Agriculture, Beijing 100193, China
| | - Qin-Qin Chen
- Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences/Key Laboratory of Agro-products Processing, Ministry of Agriculture, Beijing 100193, China
| | - Xin-Ye Wu
- Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences/Key Laboratory of Agro-products Processing, Ministry of Agriculture, Beijing 100193, China
| | - Jin-Kai Zheng
- Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences/Key Laboratory of Agro-products Processing, Ministry of Agriculture, Beijing 100193, China
| | - Shu-Rong Li
- Beijing Vocational College of Agriculture, Beijing 102442, China
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48
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Haq RU, Kumar P, Prasad K. Influence of Drying Kinetics on Moisture Diffusivity, Carotene Degradation and Nonenzymatic Browning of Pretreated and Untreated Carrot Shreds. J FOOD PROCESS PRES 2016. [DOI: 10.1111/jfpp.12785] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Raees-ul Haq
- Department of Food Engineering and Technology; Sant Longowal Institute of Engineering and Technology; Punjab India
| | - Pradyuman Kumar
- Department of Food Engineering and Technology; Sant Longowal Institute of Engineering and Technology; Punjab India
| | - Kamlesh Prasad
- Department of Food Engineering and Technology; Sant Longowal Institute of Engineering and Technology; Punjab India
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49
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Basto GJ, Carvalho CWP, Soares AG, Costa HTGB, Chávez DWH, Godoy RLDO, Pacheco S. Physicochemical properties and carotenoid content of extruded and non-extruded corn and peach palm (Bactris gasipaes, Kunth). Lebensm Wiss Technol 2016. [DOI: 10.1016/j.lwt.2015.12.065] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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50
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Mphahlele RR, Fawole OA, Makunga NP, Opara UL. Effect of drying on the bioactive compounds, antioxidant, antibacterial and antityrosinase activities of pomegranate peel. BMC COMPLEMENTARY AND ALTERNATIVE MEDICINE 2016; 16:143. [PMID: 27229852 PMCID: PMC4881059 DOI: 10.1186/s12906-016-1132-y] [Citation(s) in RCA: 80] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Accepted: 05/18/2016] [Indexed: 11/13/2022]
Abstract
BACKGROUND The use of pomegranate peel is highly associated with its rich phenolic concentration. Series of drying methods are recommended since bioactive compounds are highly sensitive to thermal degradation. The study was conducted to evaluate the effects of drying on the bioactive compounds, antioxidant as well as antibacterial and antityrosinase activities of pomegranate peel. METHODS Dried pomegranate peels with the initial moisture content of 70.30 % wet basis were prepared by freeze and oven drying at 40, 50 and 60 °C. Difference in CIE-LAB, chroma (C*) and hue angle (h°) were determined using colorimeter. Individual polyphenol retention was determined using LC-MS and LC-MS(E) while total phenolics concentration (TPC), total flavonoid concentration (TFC), total tannins concentration (TTC) and vitamin C concentration were measured using colorimetric methods. The antioxidant activity was measured by radical scavenging activity (RSA) and ferric reducing antioxidant power (FRAP). Furthermore, the antibacterial activity of methanolic peel extracts were tested on Gram negative (Escherichia coli and Klebsiella pneumonia) and Gram positive bacteria (Staphylococcus aureus and Bacillus subtilis) using the in vitro microdilution assays. Tyrosinase enzyme inhibition was investigated against monophenolase (tyrosine) and diphenolase (DOPA), with arbutin as positive controls. RESULTS Oven drying at 60 °C resulted in high punicalin concentration (888.04 ± 141.03 mg CE/kg dried matter) along with poor red coloration (high hue angle). Freeze dried peel contained higher catechin concentration (674.51 mg/kg drying matter) + catechin and -epicatechin (70.56 mg/kg drying matter) compared to oven dried peel. Furthermore, freeze dried peel had the highest total phenolic, tannin and flavonoid concentrations compared to oven dried peel over the temperature range studied. High concentration of vitamin C (31.19 μg AAE/g dried matter) was observed in the oven dried (40 °C) pomegranate peel. Drying at 50 °C showed the highest inhibitory activity with the MIC values of 0.10 mg/ml against Gram positive (Staphylococcus aureus and Bacillus subtili. Likewise, the extracts dried at 50 °C showed potent inhibitory activity concentration (22.95 mg/ml) against monophenolase. Principal component analysis showed that the peel colour characteristics and bioactive compounds isolated the investigated drying method. CONCLUSIONS The freeze and oven dried peel extracts exhibited a significant antibacterial and antioxidant activities. The freeze drying method had higher total phenolic, tannin and flavonoid concentration therefore can be explored as a feasible method for processing pomegranate peel to ensure retention of the maximum amount of their naturally occurring bioactive compounds. TRIAL REGISTRATION Not relevant for this study.
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Affiliation(s)
- Rebogile R Mphahlele
- Postharvest Technology Research Laboratory, South African Research Chair in Postharvest Technology, Department of Horticultural Sciences, Faculty of AgriSciences, Stellenbosch University, Private Bag X1, Stellenbosch, 7602, South Africa
| | - Olaniyi A Fawole
- Postharvest Technology Research Laboratory, South African Research Chair in Postharvest Technology, Department of Horticultural Sciences, Faculty of AgriSciences, Stellenbosch University, Private Bag X1, Stellenbosch, 7602, South Africa
- Postharvest Technology Research Laboratory, South African Research Chair in Postharvest Technology, Department of Food Science, Faculty of AgriSciences, Stellenbosch University, Private Bag X1, Stellenbosch, 7602, South Africa
| | - Nokwanda P Makunga
- Department of Botany and Zoology, Faculty of Science, Stellenbosch University, Private Bag X1, Stellenbosch, 7602, South Africa
| | - Umezuruike L Opara
- Postharvest Technology Research Laboratory, South African Research Chair in Postharvest Technology, Department of Horticultural Sciences, Faculty of AgriSciences, Stellenbosch University, Private Bag X1, Stellenbosch, 7602, South Africa.
- Postharvest Technology Research Laboratory, South African Research Chair in Postharvest Technology, Department of Food Science, Faculty of AgriSciences, Stellenbosch University, Private Bag X1, Stellenbosch, 7602, South Africa.
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